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Abstract:

Compositions and methods are provided for a water-soluble insecticidal or
pesticidal comprising at least one alkaloid, particularly at least one
tetracyclo-quinolizindine alkaloid derived from sophora roots,
particularly matrine and/or oxymatrine.

Claims:

1. A water-soluble insecticidal or pesticidal formulation, comprising an
insecticidally or pesticidally effective amount of at least one
tetracyclo-quinolizinindine alkaloid derived from sophora roots.

2. The formulation of claim 1 wherein said tetracycloquinolizinindine
alkaloid is oxymatrine or matrine.

[0003]Insect pests can be the cause of a significant amount of physical
and economic damage to crops around the world. In the past, conventional
pesticides, such as organophosphates, DDT and carbamates have been used
to treat these problems. However, these conventional chemicals carry
health risks as well as pest resistance issues.

[0004]Safer pesticides have recently proven to be efficacious alternatives
to conventional pesticides and have been coming into increasingly more
favor, especially amidst the vigorous adoption of organic production
methods by farmers over the past decade. Some of the broad areas of
"safer" pesticides include, but are not limited to, microbes, plant
extracts, food ingredients, etc.

[0005]Plants and plant derivatives have been used as agricultural
insecticides for thousands of years, tracing back to ancient China,
Egypt, India and Greece. (Thacker 2002. Documented use of these "natural"
pesticides well predates the advent of synthetic pesticides. Pyrethrins
are a class of insecticides derived from the pyrethrum daisy, Tanacetum
cinerariaefolium, and are characterized by a rapid knockdown effect,
particularly in flying insects, and hyperactivity and convulsions in most
insects. There are many examples of plant extracts as insecticides, some
of which are cited below.

[0006]The Indian Neem tree, Azadirachta indica, is another natural source
of insecticides. Two classes of insecticides can be extracted from Neem.
The first, Neem Oil, is effective against mites and soft-bodied insects.
The second class can be extracted from the Neem Seed, and the most potent
of these is the compound azadirachtin. Azadirachtin has been shown to
have significant physiological effects on insects, blocking the release
of molting hormones in immature insects, and causing sterility in adult
females. Azadirachtin can also act as an anti-feedant in many insects.
(Schmutterer 2002).

[0007]Azadirachtin is part of a larger group of chemicals known as
Limonoids, compounds which are known to cause bitterness in citrus
fruits. Several citrus limonoids and limonine derivatives have been found
to have insect-controlling activities, serving as insecticidal toxins and
feeding deterrents. These compounds can also kill insect larvae and
disrupt reproduction. (Roy 2006).

[0008]Rotenone is also a well known insecticide and has been in use for
over a century. It is produced in the roots of the tropical legumes
Derris, Lonchocarpus, and Tephrosia. Rotenone disrupts the electron
transport chain which is a vital step in the energy production of all
living organisms. The compound must be ingested by the insect in order to
take effect. (Hollingworth 1994).

[0009]Oxymatrine is a substance found in Sophora roots and has been used
for many decades as a medicinal treatment for a variety of diseases such
as fungal and parasitic infections, cancer, arrhythmias, skin problems
and many others, and most recently for Hepatitis B and C (Kuizhi, Niu,
1997). The volume of current research in this area is intense. Although
the medicinal properties of oxymatrine have been thoroughly evaluated,
its ability to exhibit insecticidal activity has received very little
attention by the research community.

[0010]Several processes for the preparation of oxymatrine are described in
the literature, e.g., Chinese Pat. Nos. CN1148370C (C). Typically,
oxymatrine is extracted from the root, leaf, stem or seed of sophora
plants, which seems to be the easiest way to isolate the pure product.

[0011]The known marketed formulations contain between 0.5% and 2.0%
oxymatrine or matrine. The authors of this invention used commercially
available oxymatrine from Beijing Kingbo Biotech, Inc.

[0012]In U.S. Pat. No. 6,372,239, a cocktail of plant alkaloids is
described; however, as it clearly appears said invention uses a
combination of several plant alkaloids to exert its activity via multiple
pathways, and thus is outside the scope of the present invention as will
appear from the following.

[0013]The fact is that it has now surprisingly been found that a simple
solution comprised of the active ingredients oxymatrine or matrine
provides a highly effective insecticidal formulation that can be used
against a variety of insect pests without having phytotoxic effects on
the host plant or crop.

SUMMARY OF THE INVENTION

[0014]Various studies have been directed towards assessing the
effectiveness of oxymatrine and matrine to exhibit a pesticidal,
particularly, an insecticidal effect. As a result of these studies, the
present inventor has found that a solution containing primarily
oxymatrine or matrine is an extremely effective formulation having the
desired properties.

[0015]Thus, the invention is directed to a water soluble insecticidal
formulation comprising at least one alkaloid, particularly at least one
tetracyclo-quinolizindine alkaloid derived from sophora roots,
particularly matrine and/or oxymatrine. The formulation may further
comprise water wherein oxymaterine or matrine is present in the range of
from about 0.1 to 20% by volume. In a particular embodiment, the
formulation may further comprise a non-oxymatrine, matrine, anabasine,
aloperine and/or toosendanin pesticide or insecticide. In yet another
embodiment, the formulation is a water-soluble anabasine, aloperine
and/or toosendanin free insecticidal or pesticidal formulation,
comprising an insecticidally or pesticidally effective amount of
oxymatrine and/or matrine.

[0016]The invention is further directed to a pest control method
comprising treating an object with an amount of the formulations of the
present invention effective to control pests on said object. The object
may be a plant, fruit, building or other structures. The pest may be an
insect or mite infestations.

DETAILED DESCRIPTION OF THE INVENTION

[0017]Where a range of values is provided, it is understood that each
intervening value, to the tenth of the unit of the lower limit unless the
context clearly dictates otherwise, between the upper and lower limit of
that range and any other stated or intervening value in that stated range
is encompassed within the invention.

[0018]Unless defined otherwise, all technical and scientific terms used
herein have the same meaning as commonly understood by one of ordinary
skill in the art to which this invention belongs. Although any methods
and materials similar or equivalent to those described herein can also be
used in the practice or testing of the present invention, the preferred
methods and materials are now described.

[0019]It must be noted that as used herein and in the appended claims, the
singular forms "a," "and" and "the" include plural references unless the
context clearly dictates otherwise.

[0020]A formulation that meets the requirements described above can be
economically prepared by a simple method which comprises mixing by
mechanical means commercially available oxymatrine (or matrine) and water
and/or other ingredients that are standard for insecticides, such as a
surfactant, wetting agent (e.g., organosilicones, Silwet and Sylox),
and/or dispersant. Examples of surfactants include, but are not limited
to, polyoxyethylated alkylphenols (e.g., octylphenol and nonylphenol),
polyoxyethylated sorbitan monoesters, polyoxyethylated fatty or
aryl-alkyl alcohols, fatty acids and esters (e.g. TWEEN® 40-80).

[0021]A brief description of the formulation of this invention will be
given below. The formulation of the present invention comprises the
following ingredients:

[0022]Oxymatrine and/or matrine. Water is also added; thus the formulation
also comprises water. Furthermore, various water-soluble additives in the
form of powders or granules may of course be added without changing the
nature of the present invention.

[0023]The mention of the above products excludes in no way the use of
other products with same effects according to this invention. Thus, the
formulation may further comprise other biological or chemical pesticides
except for anabasine, aloperine and/or toosendanin.

[0024]The amount of oxymatrine or matrine in the formulation of the
invention may be widely varied, and will typically be from about 0.1% to
about 20% by volume. The preferred concentration will be from about 0.5%
to about 2.0%.

[0025]The amount of formulation to be used per hectare depends on the
nature of the plant, the microclimate and the intended degree of
efficacy. Normally the rate will vary between 0.5 to 2 liters/hectare.

EXAMPLES

[0026]The following Examples demonstrate the efficacy of a 0.6%
formulation according to the present invention. The tests have been
carried out in eight different test systems:

Test System 1--Efficacy Screen--Aphid

[0027]Procedure: Test plants, Chrysanthemum vestitum stapf, were planted
into 1-quart containers in a growing medium consisting of 35% peat, 45%
aged pine bark, 15% aged rice hulls and 5% composted hardwood. No
pesticides were applied to test plants prior to study application. One
plant equals one replicate. Test plants were placed in Zone 1 of research
greenhouse on a wire-mesh raised bench and arranged in a randomized
complete block design. Research greenhouse is monitored by Procom,
Micro-Grow Greenhouse System temperature control system. Environmental
conditions averaged high temperature 87 F to low temperature of 72 F
during study dates. Average humidity levels ranged form 40% to 95%. Test
plants received natural lighting for duration of study. Test plants were
watered every twenty-four (24) hours as needed with a hand-held
sprinkler. Plants were evaluated prior to application (precount), 2 days
(48 hours) and 7 days after application. Four (4) leaves were randomly
selected and harvested on each replicate. Actual count was recorded on
live and dead aphid, Myzus persicae. Plants were evaluated for
phytotoxicity on same rating schedule as above. Visual ratings were taken
and recorded as percent of damage (0 to 100%) to whole plant as compared
to control check.

[0029]Evaluations of Green Peach Aphid at 7 days after chemical
application did show a significant decrease in the number of live aphid
in Treatment #1, Sample A as compared to number of live aphid in
Treatment #2, Untreated Check. There was no phytotoxicity on any treated
plant. Results are shown in Table I.

[0030]Objective: Efficacy screen of SAMPLE A against two-spotted
spidermite on marigold.

[0031]Procedure: Test plants, Marigold, Tagetes erecta l., were planted
into 1-quart containers in a growing medium consisting of 35% peat, 45%
aged pine bark, 15% aged rice hulls and 5% composted hardwood. No
pesticides were applied to test plants prior to study application. One
plant equals one replicate. Test plants were placed in Zone 1 of research
greenhouse on a wire-mesh raised bench and arranged in a randomized
complete block design. Research greenhouse is monitored by Procom,
Micro-Grow Greenhouse System temperature control system. Environmental
conditions averaged high temperature 87 F to low temperature of 72 F
during study dates. Average humidity levels ranged form 40% to 95%. Test
plants received natural lighting for duration of study. Test plants were
watered every twenty-four (24) hours as needed utilizing a flood floor
irrigation system. Plants were evaluated prior to application (precount),
2 days (48 hours) and 7 days after application. Three (3) leaves were
randomly selected and harvested on each replicate. Actual count was
recorded on live and dead two-spotted spidermite, Tetranychus urticae.
Plants were evaluated for phytotoxicity on same rating schedule as above.
Visual ratings were taken and recorded as percent of damage (0 to 100%)
to whole plant as compared to control check.

[0033]Conclusion: Evaluations of Two-spotted Spidermite at 7 days after
chemical application did show a significant decrease in the number of
live spidermite in Treatment #1, Sample A, as compared to number of live
spidermite in Treatment #2, Untreated Check. There was no phytotoxicity
on any treated plant.

[0034]Objective: Efficacy screen of SAMPLE A against western flower thrips
on marigold.

[0035]Procedure: Test plants, Marigold, Tagetes erecta l., were planted
into 1-quart containers in a growing medium consisting of 35% peat, 45%
aged pine bark, 15% aged rice hulls and 5% composted hardwood. No
pesticides were applied to test plants prior to study application. Three
(3) plants equal one replicate. Test plants were placed in Zone 1 of
research greenhouse on a wire-mesh raised bench and arranged in a
randomized complete block design. Research greenhouse is monitored by
Procom, Micro-Grow Greenhouse System temperature control system.
Environmental conditions averaged high temperature 85 F to low
temperature of 70 F during study dates. Average humidity levels ranged
form 45% to 100%. Test plants received natural lighting for duration of
study. Test plants were watered every twenty-four (24) hours as needed
utilizing a flood floor irrigation system. Plants were evaluated prior to
application (precount), 2 days (48 hours) and 7 days after application.
Three (3) leaves and two (2) blooms were randomly selected and harvested
on each replicate. Actual count was recorded on live and dead western
flower thrips, Frankliniella occidentalis. Plants were evaluated for
phytotoxicity on same rating schedule as above. Visual ratings were taken
and recorded as percent of damage (0 to 100%) to whole plant as compared
to control check.

[0037]Conclusion: Evaluations of Western Flower Thrips at 7 days after
chemical application did show a significant decrease in the number of
live thrips in Treatment #1, Sample A, as compared to Untreated Check.
There was no phytotoxicity on any treated plant.

[0038]Objective: Efficacy screen of SAMPLE A against silverleaf whitefly
on poinsettia.

[0039]Procedure: Test plants, Poinsettia, Euphorbia pulcherrima, were
planted into 1-quart containers in a growing medium consisting of 35%
peat, 45% aged pine bark, 15% aged rice hulls and 5% composted hardwood.
No pesticides were applied to test plants prior to study application. One
plant equals one replicate. Test plants were placed in Zone 3 of research
greenhouse on a wire-mesh raised bench and arranged in a randomized
complete block design. Research greenhouse is monitored by Procom,
Micro-Grow Greenhouse System temperature control system. Environmental
conditions averaged high temperature 87 F to low temperature of 72 F
during study dates. Average humidity levels ranged form 40% to 100%. Test
plants received natural lighting for duration of study. Test plants were
watered every twenty-four (24) hours as needed with a hand-held
sprinkler. Plants were evaluated prior to application (precount), 2 days
(48 hours) and 7 days after application. Four (4) leaves were randomly
selected on each replicate; 3/4'' plug was cut from each leaf. Actual
count was recorded on silverleaf whitefly, Bemisia argentifolii, live
nymph, dead nymph, live pupa, and dead pupa. Plants were evaluated for
phytotoxicity on same rating schedule as above. Visual ratings were taken
and recorded as percent of damage (0 to 100%) to whole plant as compared
to control check.

[0041]Conclusion: Evaluations of Silverleaf Whitefly at 7 days after
chemical application did show a significant decrease in the number of
live nymph in Treatment #1, Sample A, as compared to number of live nymph
in Treatment #2, Untreated Check. There was no phytotoxicity on any
treated plant.

Test System 5--Efficacy Screen--Cockroach

[0042]Procedure: Cockroaches, Blatella germanica, were immobilized by
using CO2 for approximately 20 seconds. Five (5) adult cockroaches
were placed in a 1.89 liter test container. One container equals one
replicate. Lid of each container has a 2''×4'' insert of screening.
A moist cotton ball was placed in each container as water source.
Cockroaches were allowed to recover for approximately 30 minutes before
treatment application was performed. Test containers were placed in
research laboratory in a randomized complete block design. Evaluation was
made on live, knockdown and dead cockroaches at 1 hour, 24 hour and 48
hour intervals after treatment application.

[0044]Conclusion: Evaluations of German cockroach at 48 hours after
chemical application did show 45% mortality in Treatment #1, Sample A as
compared to 15% mortality in Treatment #2, Untreated Check.

Test System 6--Efficacy Screen--Corn Rootworm Beetle

[0045]Procedure: Twenty (20) corn rootworm beetles, Diabrotica virgifera,
were placed in a 1.89 liter test container. One container equals one
replicate. Lid of each container has a 2''×4'' insert of screening.
A section of corn leaf was placed in each replicate as food source. Test
containers were placed in research laboratory in a randomized complete
block design. Evaluation was made on live, knockdown and dead corn
rootworm beetles at 1 hour, 24 hour and 48 hour intervals after treatment
application.

[0047]Conclusion: Evaluation of Corn Rootworm Beetle at 48 hours after
chemical application did show 85% mortality in Treatment #1, Sample A as
compared to 0.4% mortality in Treatment #2, Untreated Check.

Test System 7--Efficacy Screen--Armyworm

[0048]Procedure: Field corn, Zeamx mays l. was seeded into
3.5''×3.5'' containers in a growing medium consisting of 35% peat,
45% aged pine bark, 15% aged rice hulls and 5% composted hardwood. One
container equals one replicate. Test plants were placed in Zone 2 of
research greenhouse on a wire-mesh raised bench and arranged in a
randomized complete block design. Research greenhouse is monitored by
Procom, Micro-Grow Greenhouse System temperature control system.
Environmental conditions averaged high temperature 82 F to low
temperature of 70 F during study dates. Average humidity levels ranged
form 40% to 95%. Test plants received natural lighting for duration of
study. Test plants were watered every twenty-four (24) hours as needed
with a hand-held sprinkler. Corn plants were artificially infested with
five (5) armyworm, Pseudaletia unipuncta, 1st instar larva. Larva
was placed in leaf rolls of each replicate. After infesting each
replicate was placed on a drip plate for watering purposes. Overhead
irrigation was not utilized after infestation. Plants were evaluated 48
hours after chemical application. Damage caused by insect/pest feeding
was rated as percent damage to whole plant. Insect/pest was evaluated 48
hours after chemical application. Plants were dissected; actual count was
recorded on live armyworm. Plants were evaluated for phytotoxicity on
same rating schedule as above. Visual ratings were taken and recorded as
percent of damage (0 to 100%) to whole plant as compared to control
check.

[0051]Procedure: Field corn, Zeamx mays l. was seeded into
3.5''×3.5'' containers in a growing medium consisting of 35% peat,
45% aged pine bark, 15% aged rice hulls and 5% composted hardwood. One
container equals one replicate. Test plants were placed in Zone 2 of
research greenhouse on a wire-mesh raised bench and arranged in a
randomized complete block design. Research greenhouse is monitored by
Procom, Micro-Grow Greenhouse System temperature control system.
Environmental conditions averaged high temperature 82 F to low
temperature of 70 F during study dates. Average humidity levels ranged
form 40% to 95%. Test plants received natural lighting for duration of
study. Test plants were watered every twenty-four (24) hours as needed
with a hand-held sprinkler. Corn plants were artificially infested with
five (5) tobacco budworm, Heliothis virescent, 1st instar larva.
Larva was placed in leaf rolls of each replicate. After infesting each
replicate was placed on a drip plate for watering purposes. Overhead
irrigation was not utilized after infestation. Plants were evaluated 48
hours after chemical application. Damage caused by insect/pest feeding
was rated as percent damage to whole plant. Insect/pest was evaluated 48
hours after chemical application. Plants were dissected; actual count was
recorded on live armyworm. Plants were evaluated for phytotoxicity on
same rating schedule as above. Visual ratings were taken and recorded as
percent of damage (0 to 100%) to whole plant as compared to control
check.

[0053]Objective: Observe the mode of action and the symptoms caused by
0.6% oxymatrine on larvae of armyworms, as well as to quantify the time
required for the larvae to become paralyzed or dead.

[0054]Method: Larvae of beet armyworm were taken as first In-star stage
and placed on a microscope slide under a stereomicroscope. A drop of the
test product was delivered over them and the larvae were left to soak for
30 seconds. Excess liquid was absorbed with a paper towel and the larvae
were observed under the microscope. The products tested were Spinosad at
0.3%, Permethrin at 1%, and 0.6% oxymatrine at 800× and 1000×
dilutions. Time 1 indicates the time it took before the larva was unable
to perform normal activities like crawling, feeding, etc. Time 2 is the
additional time needed for complete elimination/death.

[0055]Spinosad, Permethrin, and 0.6% oxymatrine all work as contact
insecticides with different modes of action. [0056]Permethrin affected
the insect's basic functions in a shorter period of time (1.2 min) than
Spinosad (7.0 min) and 0.6% oxymatrine (14.0 min). [0057]There were no
significant differences between the two dilution rates of 0.6%
oxymatrine.

[0058]Although this invention has been described with reference to
specific embodiments, the details thereof are not to be construed as
limiting, as it is obvious that one can use various equivalents, changes
and modifications and still be within the scope of the present invention.

[0059]Various references are cited throughout this specification, each of
which is incorporated herein by reference in its entirety.